1. Field of the Invention
The invention relates to a vehicle body state quantity estimating device.
2. Description of Related Art
A technology of calculating pitch of a vehicle body from wheel torque calculated using a time differential value of the wheel speed is disclosed (in Japanese Patent Application Publication No. 2011-17303 (JP 2011-17303 A)). Also, a technology of ensuring the accuracy in estimation of vertical force applied from a road surface to a wheel, based on fluctuations in the wheel speed, is disclosed (in Japanese Patent Application Publication No. 2014-19252 (JP 2014-19252 A)). Further, a technology of estimating fluctuations in the vertical load on the wheel, based on fluctuations in the wheel speed, is disclosed (in Japanese Patent Application Publication No. 2014-8884 (JP 2014-8884 A)). The above-described technologies are used for estimation of vehicle body state quantities and control, such as damping control, of the vehicle based on the estimation. Here, the vehicle body state quantities include pitch, bounce, etc. of the vehicle body.
However, it is desired to estimate the vehicle body state quantities with higher accuracy, so as to control the vehicle with higher accuracy.